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1.
BMC Plant Biol ; 23(1): 562, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37964219

RESUMEN

BACKGROUND: Eucommia ulmoides leaves have high medicinal and economic value as a dual-purpose substance for medicine and food. Employing leaves from 13 natural populations of Eucommia ulmoides as research objects, this study reveals the variation patterns of intra-specific and inter-specific trait variation and explores the response of leaf characteristics to geographical and climatic changes, aiming to provide a scientific basis for the efficient utilization of leaf resources and the breeding of superior varieties. RESULTS: Descriptive statistical analysis and nested analysis of variance showed significant differences in 11 leaf traits of Eucommia ulmoides inter-populations and intra-populations, with an average coefficient of variation of 17.45%. The coefficient of variation for average leaf phenotypic traits is 20.77%, and the leaf phenotypic variation is mainly from the variation intra-populations. Principal component analysis reveals that the cumulative contribution rate of the top three principal components which mainly contributed to the phenotypic variation of Eucommia ulmoides leaves reached 74.98%, which could be sorted into size traits (34.57%), color traits (25.82%) and shape traits (14.58%). In addition, correlation analysis expresses there is a specific co-variation pattern among leaf traits, with a strong connection between shape, size, and color traits. Geographic and climatic distances are significantly correlated, and mantel test and correlation analysis indicate that leaf traits of Eucommia ulmoides are mainly influenced by altitude. With the increase of altitude, the leaves become smaller. Partial correlation analysis shows that after controlling climate factors, the correlation between some characters and geographical factors disappears significantly. Temperature and precipitation have a great influence on the variation of leaf phenotypic traits, and the larger the leaves are in areas with high temperature and heavy rainfall. CONCLUSIONS: These findings contribute to a further understanding of the leaf morphological characteristics of Eucommia ulmoides and the extent to which the environment influences leaf trait variation. They can provide a scientific basis for the protection and application of Eucommia ulmoides leaf resources in the future.


Asunto(s)
Eucommiaceae , Eucommiaceae/genética , Fitomejoramiento , Fenotipo , Variación Biológica Poblacional , Hojas de la Planta
2.
Int J Mol Sci ; 23(22)2022 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-36430929

RESUMEN

Trueperella pyogenes is an opportunistic pathogen that causes suppurative infections in animals. The development of new anti-biofilm drugs will improve the current treatment status for controlling T. pyogenes infections in the animal husbandry industry. Luteolin is a naturally derived flavonoid compound with antibacterial properties. In this study, the effects and the mechanism of luteolin on T. pyogenes biofilm were analyzed and explored. The MBIC and MBEC of luteolin on T. pyogenes were 156 µg/mL and 312 µg/mL, respectively. The anti-biofilm effects of luteolin were also observed by a confocal laser microscope and scanning electron microscope. The results indicated that 312 µg/mL of luteolin could disperse large pieces of biofilm into small clusters after 8 h of treatment. According to the real-time quantitative PCR detection results, luteolin could significantly inhibit the relative expression of the biofilm-associated genes luxS, plo, rbsB and lsrB. In addition, the in vivo anti-biofilm activity of luteolin against T. pyogenes was studied using a rat endometritis model established by glacial acetic acid stimulation and T. pyogenes intrauterine infusion. Our study showed that luteolin could significantly reduce the symptoms of rat endometritis. These data may provide new opinions on the clinical treatment of luteolin and other flavonoid compounds on T. pyogenes biofilm-associated infections.


Asunto(s)
Endometritis , Luteolina , Femenino , Humanos , Ratas , Animales , Luteolina/farmacología , Luteolina/uso terapéutico , Endometritis/tratamiento farmacológico , Biopelículas , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Flavonoides/farmacología , Flavonoides/uso terapéutico
3.
Int J Mol Sci ; 23(15)2022 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-35955509

RESUMEN

TatD960 and TatD825 are DNases that contribute to biofilm formation and virulence in Trueperella pyogenes (T. pyogenes). Luteolin is a natural flavonoid commonly found in plants that exhibits antimicrobial capacity. Our study aims to investigate the effects of luteolin on TatD DNases as a natural inhibitor. In this research, the expression of tatD genes and TatD proteins in T. pyogenes treated with luteolin was detected, and then the effect of luteolin on the hydrolysis of DNA by TatD DNases was analyzed using agarose gel electrophoresis. Moreover, the interactions between luteolin and TatD DNases were tested using surface plasmon resonance (SPR) assays and molecular docking analysis. After 1/2 MIC luteolin treatment, the transcription of tatD genes and expression of TatD proteins appeared to be reduced in 80-90% of T. pyogenes (n = 20). The gel assay revealed that luteolin can inhibit the activity of TatD DNases. The SPR assay showed that the KD values of luteolin to TatD960 and TatD825 were 6.268 × 10-6 M and 5.654 × 10-6 M, respectively. We found through molecular docking that hydrogen bonding is predominant in the interaction of luteolin and TatD DNases. Our data indicate that luteolin inhibited the ability of TatD DNases by decreasing their binding to DNA. The current study provides an insight into the development of luteolin as a DNase inhibitor in preventing biofilm formation and virulence in T. pyogenes.


Asunto(s)
Desoxirribonucleasas , Luteolina , Desoxirribonucleasas/metabolismo , Luteolina/farmacología , Simulación del Acoplamiento Molecular , Virulencia , Factores de Virulencia/genética
4.
Pak J Pharm Sci ; 33(4): 1511-1517, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33583781

RESUMEN

The extraction procedure and antioxidant activity were investigated for total proanthocyanidins extracts from Abutilon theophrasti Medic. leaves collected in August, September and October. The maximum extraction yield was achieved with 90% ethanol, 80°C of heating reflux temperature, 149.94 min of extraction time and 60(ml/g) of the ratio of solvent and material, which were optimized by Box-Behnken Design of response surface method. Spectrophotometric study displayed that total proanthocyanidins content was (0.44±0.02)% (0.52±0.01)% and (0.59±0.01)% for August, September and October samples, respectively. The proanthocyanidins extracts exhibited much stronger antioxidant activity to scavenge ABTS and DPPH free radicals, and reduce ferric power than the control synthetic antioxidant BHT. The present findings suggest that the proanthocyanidins extract from Abutilon theophrasti Medic. leaves was a very interesting candidate for the research and development of natural and healthy antioxidant for the pharmaceutical and food industries.


Asunto(s)
Antioxidantes/química , Antioxidantes/farmacología , Malvaceae/química , Hojas de la Planta/química , Proantocianidinas/química , Proantocianidinas/farmacología , Etanol/química , Flavonoides/química , Flavonoides/farmacología , Radicales Libres/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Solventes/química
5.
Biomed Chromatogr ; 33(4): e4474, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30577068

RESUMEN

The current study focused on the extraction technology, components analysis, in vitro antioxidant and antibacterial activities of total flavonoids and fatty acids from Tribulus terrestris L. fruits. The extraction process of total flavonoids and fatty acids was optimized by the response surface method, and the compositions were identified from the two extracts by HPLC-DAD-ESI-MS- and GC-MS, respectively. In addition, the antioxidant and antibacterial activities were evaluated by assay of ABTS, DPPH radical scavenging activity, ferric reducing antioxidant power and minimal inhibitory concentration. The yields of total flavonoids and fatty acids were 0.46 and 9.76% under the optimized conditions. Moreover, nine and eight compositions were identified from the two extracts based on the related references, respectively. In addition, total flavonoids and fatty acids extracts both exhibited certain antioxidant and antibacterial activities. The present findings suggest that total flavonoids extracted from T. terrestris L. fruits comprised a more interesting candidate than fatty acids for the research and development of natural and healthy antioxidants and antibacterial agents for the pharmaceutical and food industries.


Asunto(s)
Antibacterianos/análisis , Antioxidantes/análisis , Ácidos Grasos/análisis , Flavonoides/análisis , Extractos Vegetales/análisis , Tribulus/química , Antibacterianos/química , Antibacterianos/farmacología , Antioxidantes/química , Antioxidantes/farmacología , Bacterias/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Ácidos Grasos/química , Ácidos Grasos/farmacología , Flavonoides/química , Flavonoides/farmacología , Frutas/química , Cromatografía de Gases y Espectrometría de Masas , Modelos Estadísticos , Extractos Vegetales/química , Extractos Vegetales/farmacología , Espectrometría de Masa por Ionización de Electrospray
6.
Pharm Biol ; 57(1): 514-518, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31401916

RESUMEN

Context: ALI is a common disease characterized by acute pulmonary inflammatory disorder. Abutilon theophrasti Medik. (Malvaceae), as a Chinese traditional medicine, is used for the treatment of inflammation. Its main constituents are flavonoid compounds. Objective: This study investigates the regulatory effect of a TFE from Abutilon theophrasti leaves on gene expression in LPS-induced ALI mice via the NF-κB and MAPK signaling pathways. Materials and methods: Kunming mice were intragastrically administered TFE (0.25, 0.5, 1.0 g/kg) for 5 days, and then ALI was induced via intranasal administration 40 µg of LPS in 10 µL PBS after intragastric administration on the 5th day, and PBS and DEX (2 mg/kg) were negative and positive control groups, respectively. Results: The relative expression of iNOS gene was 0.707, 0.507 and 0.483 for 0.25, 0.5 and 1.0 g/kg TFE, and COX-2 gene expression was also reduced after treatment by three concentrations of TFE with 0.768, 0.545, and 0.478. The mRNA expression levels of p65 were 0.61, 0.43 and 0.27 for 0.25, 0.5 and 1.0 g/kg TFE and IκB levels were increased in a dose-dependent manner with 3.99, 13.69 and 34.36. 0.5 and 1.0 g/kg TFE inhibited the expression of ERK1/2 with 0.59 and 0.38, p38MAPK with 0.62 and 0.54, and JNK with 0.37 and 0.29, and JNK mRNA expression was 0.60 for 0.25 g/kg TFE. Discussion and conclusion: These results indicate that the regulatory mechanisms of TFE on gene expression in LPS-induced ALI mice include inhibition of the NF-κB and MAPK signaling pathways.


Asunto(s)
Lesión Pulmonar Aguda/tratamiento farmacológico , Flavonoides/farmacología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , FN-kappa B/metabolismo , Animales , Ciclooxigenasa 2/metabolismo , Medicamentos Herbarios Chinos/farmacología , Expresión Génica/efectos de los fármacos , Quinasa I-kappa B/metabolismo , Inflamación/tratamiento farmacológico , Lipopolisacáridos , Masculino , Malvaceae , Ratones , Óxido Nítrico Sintasa/efectos de los fármacos , Óxido Nítrico Sintasa/metabolismo , Hojas de la Planta , Factor de Transcripción ReIA/metabolismo
7.
Mediators Inflamm ; 2018: 3508506, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29725269

RESUMEN

The flavonoid fraction was extracted from the leaves of Abutilon theophrasti Medic., which are usually used as a traditional Chinese herbal medicine for the treatment of inflammation and joint pain. The current study focused on the extraction process, component analysis, and in vitro antioxidant, antibacterial, and anti-inflammatory activities of the flavonoid fraction as a part of ongoing research on bioactive substances from natural plant sources. This study evaluated the antioxidant activities via assays of DPPH radical scavenging capacity, ABTS radical scavenging capacity, and reducing power and investigated inhibitory activities against Escherichia coli, Salmonella, Staphylococcus aureus, and Streptococcus. Moreover, the inflammatory activity of the flavonoid fraction was estimated by measurement of the content of tumor necrosis factor alpha, interleukin-1-beta, interleukin-6, interleukin-10, nitric oxide, and cyclooxygenase-2 and the gene expression levels of several inflammation markers, such as inducible nitric oxide synthase and cyclooxygenase-2, in RAW 264.7 macrophages after LPS treatment. In addition, the underlying anti-inflammatory mechanisms, that is, the activation of nuclear factor kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways, were also revealed from the gene and protein expression levels. Taken together, these results suggested that the flavonoid fraction might exert in vitro antioxidant, antibacterial, and anti-inflammatory effects on LPS-stimulated RAW 264.7 macrophages and will be potentially useful as an adjuvant treatment for oxidative stress and bacterial and inflammatory diseases.


Asunto(s)
Antibacterianos/química , Antibacterianos/farmacología , Antiinflamatorios/química , Antiinflamatorios/farmacología , Antioxidantes/química , Antioxidantes/farmacología , Flavonoides/química , Flavonoides/farmacología , Animales , Supervivencia Celular/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Interleucina-6/metabolismo , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones , FN-kappa B/metabolismo , Extractos Vegetales/química , Extractos Vegetales/farmacología , Hojas de la Planta/química , Células RAW 264.7 , Salmonella/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Streptococcus/efectos de los fármacos , Espectrometría de Masas en Tándem , Factor de Necrosis Tumoral alfa/metabolismo
8.
J Dairy Sci ; 101(1): 572-580, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29055550

RESUMEN

Bovine mastitis is still a central problem on dairy farms despite control programs, and Escherichia coli is a crucial pathogen during the development of bovine mastitis. The virulence genes, antimicrobial susceptibility, and mortality of mice infected with different E. coli isolates from bovine mastitis were determined in this study. According to the presence of the specific genes chuA, yjaA, and TspE4.C2, these isolates mainly belonged to 2 different groups: group A (47/79) and group B1 (22/79). The ompC gene was detected in all the isolates, followed by fimH (89.9%), ECs3703 (88.6%), and ompF (73.4%), whereas most of the virulence genes were not detected in these isolates. The results of the antimicrobial susceptibility tests indicated that the isolates were susceptible to the fluoroquinolones and aminoglycosides. An inverse relationship was shown between the expression level of ompF and antimicrobial resistance; additionally, the isolates that were nonsusceptible to at least 4 classes of antimicrobial agents showed a lower mortality to mice in comparison with the susceptible isolates. This study indicated that antibiotic resistance had emerged in E. coli from bovine mastitis in this area, and appropriate measures should be taken to avoid potential threats to humans and other animals.


Asunto(s)
Antiinfecciosos/farmacología , Farmacorresistencia Bacteriana/genética , Infecciones por Escherichia coli/veterinaria , Escherichia coli/genética , Mastitis Bovina/microbiología , Aminoglicósidos/farmacología , Animales , Bovinos , Escherichia coli/efectos de los fármacos , Escherichia coli/aislamiento & purificación , Escherichia coli/patogenicidad , Infecciones por Escherichia coli/tratamiento farmacológico , Infecciones por Escherichia coli/microbiología , Proteínas de Escherichia coli/genética , Femenino , Fluoroquinolonas/farmacología , Mastitis Bovina/tratamiento farmacológico , Ratones , Filogenia , Virulencia , Factores de Virulencia/genética
9.
Microb Pathog ; 105: 51-56, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28188901

RESUMEN

Trueperella pyogenes plays a crucial role in endometritis pathogenesis and is also associated with many infections, including metritis, mastitis, arthritis and liver abscessation, in many domestic animals. In this study, we investigated the prevalence of tetracycline resistance in T. pyogenes isolated from dairy cows with endometritis in Inner Mongolia, China, and we assessed tetracycline-resistance gene distribution among the isolates. Our results indicated that 68.7% and 62.5% of the isolates were resistant to tetracycline and doxycycline, respectively, and the rate of resistance to metacycline was 18.8%. The tetracycline resistance gene tetK was present in all isolates (n = 32), whereas the tetM gene was identified in 12.5% and 9.4% of the isolates, in the chromosome and plasmid, respectively. Strains carrying tetW were also common in the chromosome and plasmid, with abundances of 53.1% and 46.9%, respectively. However, tetO and otrA were absent in all isolates. The resistance phenotype analysis indicated that 6.3% of strains were susceptible to all tetracyclines, while 3.1% showed resistance to all tetracyclines.


Asunto(s)
Actinomycetaceae/aislamiento & purificación , Enfermedades de los Bovinos/epidemiología , Enfermedades de los Bovinos/microbiología , Endometritis/veterinaria , Resistencia a la Tetraciclina , Actinomycetaceae/efectos de los fármacos , Actinomycetaceae/genética , Animales , Antibacterianos/farmacología , Bovinos , China/epidemiología , Cromosomas Bacterianos , Endometritis/epidemiología , Endometritis/microbiología , Femenino , Genes Bacterianos , Plásmidos , Prevalencia , Tetraciclinas/farmacología
10.
Acta Pol Pharm ; 74(3): 881-890, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-29513957

RESUMEN

This paper described the extraction procedure and determination method for the total flavonoids in ethanol extract from the leaves of Abutilon theophrasti Medic., and evaluated antibacterial and antioxidant activity. Maximum extraction yield was achieved using 60% ethanol, 1 : 30 (g/mL) of a ratio of material to solvent, 20 min of extraction time, 40 kHz of ultrasonic frequency, 100 W of ultrasonic power, 600C of extraction temperature and two extraction cycles. Total flavonoids content was 16.79 RE mg/g medicinal materials. The extracts had effective antibacterial activity against 24 test strains from S. aureus and E. coli, MICs ranged from 2.18 to 8.7 mg/mL; it was also revealed that the extracts demonstrated high flavonids content and potent antioxidant activity, achieved by hydroxyl radical, DPPH radical and ABTS radical scavenging. These results indicated thathe extract may be a promising plant demonstrating antibacterial and antioxidant activities.


Asunto(s)
Antibacterianos/farmacología , Antioxidantes/farmacología , Etanol/química , Malvaceae/química , Extractos Vegetales/farmacología , Hojas de la Planta/química , Solventes/química , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Benzotiazoles/química , Compuestos de Bifenilo/química , Relación Dosis-Respuesta a Droga , Escherichia coli/efectos de los fármacos , Escherichia coli/crecimiento & desarrollo , Radical Hidroxilo/química , Pruebas de Sensibilidad Microbiana , Viabilidad Microbiana/efectos de los fármacos , Fitoterapia , Picratos/química , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Plantas Medicinales , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrollo , Ácidos Sulfónicos/química
11.
Pak J Pharm Sci ; 30(3): 767-772, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28653920

RESUMEN

This paper described the extraction procedure of six extracts from Abutilon theophrasti Medic. leaves and evaluated antioxidant and antibacterial activity of different extracts by hydroxyl radical, DPPH radical scavenging, broth micro-dilution and agar-well diffusion methods. The six extracts were prepared by the two extraction procedures: (I) water was the extraction solvent; (II) 90% alcohol extract was extracted by petroleum ether, chloroform, ethyl acetate and n-butanol in turn. Extract yields were 7.34%, 7.31%, 0.45%, 0.12%, 2.70% and 5.68% for extract I to VI. It was revealed that the various extracts had effective antibacterial activity against four test strains from Staphylococcus aureus (ATCC 25923), Streptococcus (ATCC 49619), Escherichia coli (ATCC 25922) and Salmonella (ATCC 01303); meanwhile, the six extracts demonstrated potent antioxidant activity, achieved by hydroxyl radical and DPPH radical scavenging assay. Minimum inhibitory concentrations (MICs) for the bacterial species ranged from 2.21 to 539.46 mg/ml, diameter of inhibition zone ranged from 2.08 to 15.05mm. The scavenging •OH and DPPH• rates were 62.37% to 81.86% with the concentration 0.06 to 1.89mg/ml and 37.80% to 81.23% with the concentration 1.07 to 35.52mg/ml. According to the results, these extracts have antioxidant and antibacterial activity. In view of all the facts collectively, the six extracts will become natural and nontoxic antioxidant and antibacterial agent, and be applied in food and pharmaceutical industries for the prevention or treatment caused by microorganisms and free radicals.


Asunto(s)
Antibacterianos/farmacología , Antioxidantes/farmacología , Malvaceae/química , Extractos Vegetales/farmacología , Solventes/química , Bacterias/efectos de los fármacos , Pruebas de Sensibilidad Microbiana
12.
Microb Pathog ; 71-72: 20-4, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24803199

RESUMEN

Virulence could be modulated by many instinctive and environmental factors including oxygen, osmolarity and antimicrobial agents. This study aimed to investigate the correlation between drug resistance and the nanH expression in Trueperella pyogenes (T. pyogenes). Minimum inhibitory concentrations (MICs) of 6 ß-lactam antimicrobial agents (penicillin G, amoxicillin, oxacillin, cefazolin, ceftiofur, and ampicillin) against T. pyogenes were tested by standard broth dilution method according to the protocols of the Clinical and Laboratory Standards Institute (CLSI), and real-time fluorescent quantitative reverse transcription-polymerase chain reaction (RT-PCR) was selected to investigate the mRNA expression levels of the nanH in T. pyogenes. All the isolates were resistant to atleast 2 of antimicrobial agents, and multidrug resistance (resistance to atleast 3 antimicrobials) was observed in 84.38% (27/32) of isolates. The mRNA expression levels of the nanH were significantly higher in comparison with that in ATCC19411, as the resistance profile enlarged, the nanH mRNA expression levels decreased in T. pyogenes. These results indicated that ß-lactam antibiotic resistance in T. pyogenes may alter the expression of the nanH.


Asunto(s)
Actinomycetaceae/efectos de los fármacos , Antibacterianos/farmacología , Proteínas Bacterianas/biosíntesis , Enfermedades de los Bovinos/microbiología , Endometritis/veterinaria , Resistencia betalactámica , beta-Lactamas/farmacología , Actinomycetaceae/genética , Actinomycetaceae/aislamiento & purificación , Animales , Bovinos , Endometritis/microbiología , Femenino , Expresión Génica , Pruebas de Sensibilidad Microbiana , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
13.
Front Chem ; 11: 1186711, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37090243

RESUMEN

As global ageing deepens and galanthamine is the preferred clinical drug for the treatment of mild to moderate Alzheimer's disease, it will be valuable to examine the behaviour and mechanism of galanthamine's thermal decomposition for its quality control, formulation process, evaluation of thermal stability, and expiry date in production. In order to study the pyrolysis of galanthamine hydrobromide with nitrogen as the carrier gas, a thermogravimetric-differential thermogravimetric technique (TG-DTG) was applied at a temperature rise rate of 10 K min-1 and a volume flow rate of 35 mL min-1. The apparent activation energy E a and the prefactor A (E a = 224.45 kJ mol-1 and lnA = 47.40) of the thermal decomposition reaction of galanthamine hydrobromide were calculated according to the multiple heating rate method (Kissinger and Ozawa) and the single heating rate method (Coats-Redfern and Achar), and the most probable mechanism function was derived, and then the storage period was inferred from E a and E. A three-dimensional diffusion mechanism was suggested to control the thermal decomposition of galanthamine hydrobromide in accordance with the Jander equation, random nucleation and subsequent growth control, corresponding to the Mample one-way rule and the Avrami-Erofeev equation. As a result, the thermal decomposition temperature of galanthamine hydrobromide gradually increased with the rate of temperature rise. From Gaussian simulations and thermogravimetric data, galanthamine hydrobromide decomposed at the first stage (518.25-560.75 K) to release H2O, at the second stage (563.25-650.75 K) to generate CO, CO2, NH3 and other gases, and finally at the third stage (653.25-843.25 K) to release CO2. After 843.25 K, the residual molecular skeleton is cleaved to release CO2 and H2O. According to the E a and A presenting in the first stage of thermal decomposition, it is assumed that the storage life of galanthamine hydrobromide at room temperature 298.15 K is 4-5 years.

14.
Colloids Surf B Biointerfaces ; 229: 113435, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37437413

RESUMEN

Inorganic antibacterial nanomaterials play an increasingly important role in addressing the growing threat of drug-resistant bacteria. Graphene oxide-silver nanoparticles composite (GO-AgNPs), as a kind of inorganic nanomaterials, have excellent antibacterial properties, showing promising potential in biomedical field. However, GO-AgNPs are terribly prone to sedimentation due to aggregation in physiological solutions, along with its non-environmental issues during the synthesis process, seriously limits the antibacterial application of GO-AgNPs in the biomedical field. To solve this problem, herein, polyethylene glycol-graphene oxide-silver nanoparticles composite (GO-AgNPs-PEG) were prepared by modifying GO-AgNPs with polyethylene glycol to enhance their dispersion stability in physiological solutions. In addition, GO-AgNPs-PEG were prepared with using the natural product gallic acid as a reductant and stabilizer, exhibiting the characteristic of environmentally friendly. Meanwhile, the dispersion stability and antibacterial activity of GO-AgNPs-PEG were characterized by various technical methods, it was found that GO-AgNPs-PEG can be stably dispersed in a variety of physiological solutions (e.g., physiological saline, phosphate buffer solution, Luria-Bertani medium, Murashige and Skoog medium) for more than one week. Moreover, the antibacterial properties of GO-AgNPs-PEG in physiological solutions were significantly better than those of GO-AgNPs. Furthermore, it was discovered that the antibacterial mechanism of GO-AgNPs-PEG was probably associated to destroying the integrity of bacterial cell walls and membranes. The findings in this work can provide new ideas and references for the development of new inorganic antibacterial nanomaterials with stable dispersion in physiological solutions.


Asunto(s)
Nanopartículas del Metal , Nanocompuestos , Polietilenglicoles , Plata/farmacología , Antibacterianos/farmacología
15.
Fitoterapia ; 170: 105630, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37536471

RESUMEN

Artemisia anomala S. Moore exerts many pharmacological activities, including the removing of the blood stasis, relieving of the fever and analgesia, reducing the swelling and dampness. In this study, the extraction technology, chemical compositions and anti-inflammatory effect in vitro and mechanism of total flavonoids extract from Artemisia anomala S. Moore were studied. The optimal yield rate of total flavonoids extract was optimized by single factor experiments and response surface method, and the chemical constituents were analyzed by UPLC-QTOF-MS method; and the anti-inflammatory activity of the extract was evaluated with lipopolysaccharide induced RAW 264.7 cells. The highest extraction rate was 2.02% under these conditions of the concentration of ethanol 50%, the ultrasonic extraction time 30 min, and the ratio of solvent volume to material weight 20:1 (ml/g). In addition, the main components of total flavonoid extract were preliminarily identified and deduced based on mass spectrometry information and relevant literatures, and its stronger anti-inflammatory activity was demonstrated by reducing the phagocytosis, the content of nitric oxide and the level of related cytokines (tumor necrosis factor-α, interleukin-10, interleukin-6). Furthermore, it was further revealed that the anti-inflammatory effect of the extract was closely connected with the activation of TLR4-MyD88-NF-κB signalling pathway. This study indicated that the total flavonoids extract from Artemisia anomala S. Moore may be a better candidate anti-inflammatory natural medicine.

16.
J Sep Sci ; 35(5-6): 763-72, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22275244

RESUMEN

A rapid and resolutive reverse-phase high-performance liquid chromatography-electrospray ionization-quadrupoles-time of flight-mass spectrometry method was established for the screening and identification of the phenolic compounds in the 70% ethanolic extracts from the five parts (roots, stems, leaves, seeds, and exocarps) of Abutilon theophrasti Medic.. Separation and detection conditions were optimized by using a 22 mixing standard, which included phenolic acids, flavonoids and a naphthalene compound. Optimum LC separation was achieved on a C(18) analytical column (250 mm x 4.6 mm id, 5 µm) by gradient elution with water containing 0.1% v/v formic acid (pH 2.4) and acetonitrile as mobile phases, at a flow rate of 1.0 mL/min. The developed method was applied to the study on the constituents of A. theophrasti Medic., and 16 compounds were unequivocally identified with standards. Meanwhile, 37 constituents were tentatively identified by comparing with references. In addition, accurate molecular formulae were conjectured for unknown compounds. To our knowledge, little is known about how these compounds are distributed in A. theophrasti Medic.. Hence, it is clear that the comprehensive analysis of the phenolic compounds of A. theophrasti Medic. is helpful for the quality control and understanding the usage and function of the herb and its products.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Malvaceae/química , Fenoles/química , Extractos Vegetales/química , Espectrometría de Masa por Ionización de Electrospray/métodos , Cromatografía de Fase Inversa/métodos , Estructuras de las Plantas/química
17.
Front Chem ; 10: 905781, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35572121

RESUMEN

The adoption of plant-derived natural products to synthesize metal nanoparticles and their complexes has the advantages of mild reaction conditions, environmental protection, sustainability and simple operation compared with traditional physical or chemical synthesis methods. Herein, silver nanoparticles (AgNPs) were in situ synthesized on the surface of graphene oxide (GO) by a "one-pot reaction" to prepare graphene oxide-silver nanoparticles composite (GO-AgNPs) based on using AgNO3 as the precursor of AgNPs and gallic acid (GA) as the reducing agent and stabilizer. The size and morphology of GO-AgNPs were characterized by ultraviolet-visible spectrophotometer (Uv-vis), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscope (TEM), X-ray diffractometer (XRD) and dynamic light scattering (DLS). The effects of pH, temperature, time and material ratio on the synthesis of GO-AgNPs were investigated experimentally. The results showed that ideal GO-AgNPs could be prepared under the conditions of pH = 9, 45°C, 2 h and the 2:1 of molar ratio of AgNO3 to GA. The AgNPs within GO-AgNPs are highly crystalline spherical particles with moderate density on the surface of GO, and the size of AgNPs is relatively uniform and determined to be about 8.19 ± 4.21 nm. The research results will provide new ideas and references for the green synthesis of metal nanoparticles and their complexes using plant-derived natural products as the reducing agent and stabilizer.

18.
J Pharm Biomed Anal ; 209: 114480, 2022 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-34839052

RESUMEN

Rutin is a flavonoid compound with many pharmacological activities, including antioxidation, anti-inflammation and cardiovascular and cerebrovascular protection. However, there are great limitations in clinical application in view of its poor solubility and slow absorption in vivo. In this study, a pharmacokinetic and pharmacodynomic model was adopted to study the correlation of the pharmacokinetics and pharmacodynomics of rutin in lipopolysaccharide-induced acute lung injury mice. Rutin was intragastrically administered continuously for 5 days at a dose of 200 mg/kg/d, and pharmacokinetic and pharmacodynamic indicators were measured every day after administration, including the blood concentration of rutin, the W/D ratio of lungs, the nitric oxide content and the expression levels of TLR4, TRAF6, IκB and P-IκB proteins. The results indicated that rutin can exert an anti-inflammatory protective effect by improving lung tissue injury, significantly decreasing the synthesis of the inflammatory mediator nitric oxide, and inhibiting the protein expression levels of TLR4, TRAF6 and P-IκB. The absorption of rutin conformed to a one-compartment model with the pharmacokinetic parameters as follows: t1/2α= 9.76 h, t1/2ß= 19.44 h, Tmax= 24.00 h, Cmax= 22.65 µg/ml and AUC(0-t)= 518.58 µg/ml·h. A PK-PD combination model was established to fit the optimal administration time of rutin with a one-compartment-Sigmod Emax model connected to the effect site. Meanwhile,the PK-PD combination model was a better approach for evaluating the relationships between the five pharmacodynamic indicators and the pharmacokinetic characteristics of rutin. The correlation between the pharmacokinetics and pharmacodynamics of rutin was quantitatively analysed to provide a theoretical basis for the research and development of new anti-inflammatory drugs in clinical practice.


Asunto(s)
Lesión Pulmonar Aguda , Rutina , Lesión Pulmonar Aguda/inducido químicamente , Lesión Pulmonar Aguda/tratamiento farmacológico , Lesión Pulmonar Aguda/prevención & control , Animales , Antiinflamatorios/uso terapéutico , Antioxidantes/uso terapéutico , Lipopolisacáridos/uso terapéutico , Lipopolisacáridos/toxicidad , Ratones
19.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 9): o2328, 2011 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-22058953

RESUMEN

In the title compound, C(19)H(19)NO(5), the furan-one unit makes a dihedral angle of 30.93 (6)° with the benzene ring and a dihedral angle of 9.51 (6)° with the aniline ring. In the crystal, inter-molecular C-H⋯O hydrogen bonds and C-H⋯π contacts link the mol-ecules into sheets. A weak intramolecular hydrogen bond is also observed.

20.
Zhong Yao Cai ; 34(10): 1608-11, 2011 Oct.
Artículo en Zh | MEDLINE | ID: mdl-22372153

RESUMEN

OBJECTIVE: To study the aqueous two-phase system which could be used for extraction of berberine hydrochloride. METHODS: Three aqueous two-phase systems were used for extraction experiment firstly, the best one was chosen from that, and then the single factor experiment and orthogonal experiment were carried out. RESULTS: 10 mL 95% ethanol with 10 mL 2.2 mol/L ammonium sulfate could make a aqueous two-phase system, added 600 mg berberine hydrochloride whose purity was 53.22% into it, regulated its pH to 4, then the system was put into water-bath heater (70 degrees C) for 30 min, the extraction rate could reach 99.29%; Collected the extraction liquid, dried it under 40 degrees C, the purity of berberine hydrochloride was 88.43%. CONCLUSION: This system is a suitable aqueous two-phase system for extraction of berberine hydrochloride.


Asunto(s)
Sulfato de Amonio/química , Antibacterianos/aislamiento & purificación , Berberina/aislamiento & purificación , Etanol/química , 2-Propanol/química , Antibacterianos/química , Berberina/química , Cromatografía Líquida de Alta Presión/métodos , Concentración de Iones de Hidrógeno , Solventes/química , Tecnología Farmacéutica/métodos , Temperatura
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